12,694,872 research outputs found
Tracer of electrical conduit or pipes
Device matches ends of a buried conduit, transversing an inaccessible area, without cutting the current
Hamilton's theory of turns revisited
We present a new approach to Hamilton's theory of turns for the groups
SO(3) and SU(2) which renders their properties, in particular their
composition law, nearly trivial and immediately evident upon inspection.
We show that the entire construction can be based on binary rotations rather
than mirror reflections.Comment: 7 pages, 4 figure
Corona-type theorems and division in some function algebras on planar domains
Let be an algebra of bounded smooth functions on the interior of a
compact set in the plane. We study the following problem: if
satisfy , does there exist
and a constant such that ? A
prominent role in our proofs is played by a new space, C_{\dbar, 1}(K), which
we call the algebra of \dbar-smooth functions.
In the case , a complete solution is given for the algebras of
functions holomorphic in and whose first -derivatives extend
continuously to \ov{K^\circ}. This necessitates the introduction of a special
class of compacta, the so-called locally L-connected sets.
We also present another constructive proof of the Nullstellensatz for ,
that is only based on elementary \dbar-calculus and Wolff's method.Comment: 23 pages, 6 figure
Ratemeter
An instantaneous reading tachometer in which reoccurring events to be measured in rate, trigger a threestate timing generator in which the first two states are of fixed duration and the third state is of variable duration is described. An electrical decay circuit is set to a reference level by the second state and the third state causes this reference level to decay until the reoccurrence of an event. This triggers a new first state which in turn triggers a sample and hold circuit to hold the decayed level. The decayed level is amplified and provided as an output indicative of the instantaneous rate of occurence of the last two successive events
Reduced Persistence Length and Fluctuation-Induced Interactions of Directed Semiflexible Polymers on Fluctuating surfaces
We consider directed semiflexible polymers embedded in a fluctuating surface
which is governed by either surface tension or bending rigidity. The attractive
interactions induced by the fluctuations of the surface reduce the rigidity of
the polymers. In particular, it is shown that for arbitrarily stiff parallel
polymers, there is a characteristic separation below which they prefer to bend
rather than stay linear. The out-of plane fluctuations of the polymer, screen
out the long-range fluctuation-induced forces, resulting in only a short-ranged
effective attraction.Comment: REVTEX, one postscript figur
Strong-Coupling Theory for Counter-Ion Distributions
The Poisson-Boltzmann approach gives asymptotically exact counter-ion density
profiles around charged objects in the weak-coupling limit of low valency and
high temperature. In this paper we derive, using field-theoretic methods, a
theory which becomes exact in the opposite limit of strong coupling. Formally,
it corresponds to a standard virial expansion. Long-range divergences, which
render the virial expansion intractable for homogeneous bulk systems, are shown
to be renormalizable for the case of inhomogeneous distribution functions by a
systematic expansion in inverse powers of the coupling parameter. For a planar
charged wall, our analytical results compare quantitatively with extensive
Monte-Carlo simulations.Comment: 7 pages, 3 figures; to appear in Europhys. Let
Flavour mixing and mass matrices via anticommuting properties
Five anticommuting property coordinates can accommodate all the known
fundamental particles in their three generations plus more. We describe the
points of difference between this scheme and the standard model and show how
flavour mixing arises through a set of expectation values carried by a single
Higgs superfield.Comment: 12 pages, LaTe
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